Mittwoch, 25. Februar 2015

TP-LINK TL-WN725N v2 working on Raspberry Pi (Raspbian)

A few days back I got my first Raspberry Pi. To make things easier, I bought a starter pack which contained – among others – a small Wifi adapter TL-WM725N from TP-Link.

As it turned out, this USB device does not work out-of-the-box with the current version of Raspbian. According to the sources listed below, the TL-WM725N once did work without problems with the Raspberry Pi until the new and shiny version 2 of the TL-WM725N was released. It seems that this fact slipped by the vendor of this starter pack.

The USB ID of this particular Wifi adapter is: 0bda:8179

The current version (Feb. 2015) of the kernel, as returned by uname -a is:
Linux raspberrypi 3.18.7+ #758 PREEMPT Mon Feb 23 19:27:03 GMT 2015 armv6l GNU/Linux

dmesg showed this message:

[   23.690020] r8188eu 1-1.4:1.0: Direct firmware load for rtlwifi/rtl8188eufw.bin failed with error -2
[   23.690072] r8188eu 1-1.4:1.0: Firmware rtlwifi/rtl8188eufw.bin not available


The most helpful posting on this topic was this one. It contains a link to a ZIP file and instructions to install it.

The ZIP files contains firmware for the Wifi adapter and a kernel module.

Contrary to the claims of the author of the blog post, the firmware was missing in my version of Raspbian. On the other hand the kernel module is not needed. This is a good thing because kernel modules depend on a specific kernel version and the one in the ZIP file is outdated and must not be installed. It would delete the existing module which is complaining about the missing firmware.

Which means, I only had to copy the firmware (rtl8188eufw.bin):

wget https://dl.dropboxusercontent.com/u/80256631/8188eu-20140307.tar.gz
tar -zxvf 8188eu-20140307.tar.gz
sudo cp rtl8188eufw.bin /lib/firmware/rtlwifi
sudo reboot


The dropbox link may vanish any time. A better solution would be appreciated.

As an alternative that should run out of the box, this blog post suggests the EDIMAX EW-7811U.


Links
  • http://laurenthinoul.com/how-to-install-tp-link-tl-wn725n-on-raspberry-pi/
  • http://www.mendrugox.net/2013/08/tp-link-tl-wn725n-v2-working-on-raspberry-raspbian/
  • http://blog.pi3g.com/2013/05/tp-link-150mbps-wireless-n-nano-usb-adapter-tl-wn725n-und-raspberry-pi/ (german)
  • http://www.amazingcode.de/tp-link-tl-wn725n-auf-raspbian/ (german)